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Use the extra configuration item.
Memory
Set by the memory configuration item. Numeric only (no M or G suffix allowed). Units are MB (or MiB?).
vif
vif (Default=[]; Value="type=TYPE, mac=MAC, bridge=BRIDGE, ip=IPADDR, script=SCRIPT," + \ "backend=DOM, vifname=NAME, rate=RATE, model=MODEL, accel=ACCEL" )
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